In patients with chronic hepatitis C, the ultimate treatment goal is the improvement of liver histology and inhibition of progression to liver cirrhosis and hepatocellular carcinoma (HCC). These effects are reported to be correlated with sustained ALT improvement. Therefore, the aim of this study is to determine if a low-dose (0.25, 0.5, or 1.0 mcg/kg SC QW) PegIntron monotherapy administered for 12 weeks will result in ALT normalization in Japanese patients with chronic hepatitis C.

Inclusion Criteria:

Patients with chronic hepatitis C patients (CHC) who met all of the following criteria:

• At least 20 years of age and willing to sign an informed consent
• Patients who can practice contraception
• Patients who are classified either as relapsers or non-responders.
• Weight between 45 and 100 kg
• Patients willing to be hospitalized for 3 days after the start of treatment
• Patients with positive HCV-RNA
• Serum ALT level: Over 60 IU/L, equal to or less than 150 IU/L
• Neutrophil count: equal to or more than 1,200 /mm^3
• Platelet count：equal to or more than 100,000/mm^3

Exclusion Criteria:

• Patients with conditions which would interfere with the evaluation of therapeutic efficacy of the study drug and patients for whom assurance of safety is a concern were excluded from the study.